Electrical connector contact crimping tool



March 9, 1965 J. E. MORRIS ELECTRICAL CONNECTOR CONTACT CRIMPING TOOL 2 Sheets-Sheet 1 Original Filed Aug. 27, 1958 H 5 8 3 9% 3 3 wwmw T 5 R I V mm A, 6 mm INVENTOR.

JAMES E. MORRIS g-m hi; 3

Attorney March 9, 1965 J. E. MORRIS 3,172,211

ELECTRICAL CONNECTOR CONTACT CRIMPING TOOL Original Filed Aug. 27, 1958 2 Sheets-Sheet 2 INVENTOR.

JAMES E. MORRIS Attorney United States Patent 3,172,211 ELECTRICAL CONNECTOR CONTACT CBIG TGOL James E. Morris, Fort Worth, Tex., assignor to General Dynamics Corporation (Cpnvair Division), San Diego, Calif., a corporation of Delaware Original application Aug. 27, N58, Ser. No. 757,514, new Patent No. 33359511, dated Oct. 23, 1962. Divided and this application Feb. 9, 1962, Ser. No. 172,195 5 Claims. (Cl. 33-481) This application is a division of applicants co-pending application Serial No. 757,514 filed August 27, 1958, now Patent No. 3,059,511. This invention relates to crimping tools and more particularly to crimping tools which automatically apply the required amount of pressure for securing connectors to various size wires and which position the crimp along the axis of the contact as desired.

Heretofore crimping tools have been used for making crimps in a connector barrel to secure it to an electrical conductor. This provides for physical and electrical contact without the necessity of soldering. However, care must be exercised to insure that a crimp of suilicient depth has been made to prevent accidental disengagement of the connector with the conductor. Also, if excessive pressure is applied, the connector barrel becomes distorted and its Walls may become out or broken. Since the connector has a barrel portion to receive the conductor and a pin portion extension which will not receive the conductor, the position of the crimp along the connector axis must be accurate in order to insure crimping action with the conductor. Additional crimping of the connector to the insulation on the conductor for greater strength is sometimes desirable, requiring a second crimping spaced along the connector axis from the first crimp. While a length adjustment attachment for crimping tools is currently available, it requires that a connector well nut be manually adjusted until the centerline of the nut is properly set This requires continuous adjustment in placing more than one crimp axially along the connector.

The connector contact crimping tool comprising the present invention provides for a ratchet mechanism to prevent withdrawal of the connector from the punch holder until the handles of the tool have been completely closed to insure sufficient crimping action regardless of the size of the wire and connector being crimped. A clutch mechanism is provided to lhnit the crimping pressure applied against the connector so that excessive pressure will not break, out or unduly distort the connector, irrespective of its size. This is done by stopping further inward movement of the punches against the connector with continued inward movement of the handles. A depth selector with a positive stop is provided to accommodate various lengths of connector pins and barrels. For connectors requiring a second axial crimp, a trigger mechanism is provided to readily permit a positive predetermined axial spacing of the second crimp from the first. Once the tool is set for crimping of a certain depth no further adjustment is necessary and connectors and conductors may be crimped together in a speedy mass production manner without adjustment to provide for their size.

It is therefore an object of the present invention to provide for a new and improved crimping tool.

Another object is the provision of a crimping tool which automatically applies a uniform pressure to connectors and conductors irrespective of their various sizes.

Another object is the provision of a crimping tool wherein a predetermined minimum crimping pressure must be applied before the tool punches may be with- 3,172,?2l l Patented Mar. 9, 1965 drawn from contact with the connector being crimped to its associated conductor.

Another object is the provision of a crimping tool wherein excessive pressure will operate a clutch release to prevent crimping too deeply, thereby cutting, breaking or unduly distorting the connector being crimped.

Another object is the provision of a crimping tool having a plurality of quickly adjustable positive stops for axially positioning the crimping of a connector at predetermined distances from its tip.

Another object is the provision of a crimping tool having a stop release to permit the crimping of a connector in axial spaced relation from a first crimp.

Another object is the provision of a crimping tool which automatically applies a pressure within predetermined minimum and maximum limits to all sizes of connectors and conductors within wire sizes #28 through #10 without manual adjustment for crimp indentions.

Other objects and features of the present invention will be readily apparent to those skilled in the art from the following specification and appended drawings wherein is illustrated a preferred from of the invention, and in which:

FIGURE 1 is a side elevational view with portions thereof broken away to better illustrate tool operation,

FIGURE 2 is a top plan view showing the depth selector mounting, and

FIGURE 3 is an exploded perspective view of the depth selector mechanism.

This invention relates generally to an improved crimping tool of the type having two relatively movable handle members 11 and 12 adapted to be pivotally connected at one of their extremities. Handle member 11 is generally U-shaped in section formed by a body portion 13 and a pair of side plates 14, 16 which have enlarged section 17 at the pivotal extremity. These plates have aligned openings 18 for receiving the connector to be crirnped. Slotted openings 19 are arranged symmetrically about and spaced radially from the central opening 18 and are designed to accommodate fastening units 21 such as bolts, rivets or the like when the component parts of the tool are assembled. Handle member 12 has a structural configuration similar to that of handle member 11 except that it is preferably constructed of solid material, such as cast iron for example, and its enlarged extremity 22 is adapted to fit between plates 14, 16. This enlarged extremity 22 has an enlarged opening 23 whose cent-er is in axial alignment with the center of opening 18 in the plates 1 16. This opening 23 in handle member 12 has a series of cam surfaces 2 about its periphery.

A cylindrical punch holder 26 is adapted to rotate within the enlarged opening 23. This punch holder 26 also has a central opening 27 in axial alignment with the other opening 18 to accommodate the connector inserted therein. Extending radially from the central opening 27 of the punch holder 26 and intermediate the side walls thereof are a series of passageways Z8, preferably four in number spaced at ninety degree intervals. These passageways 28 are preferably circular in section and contain a shoulder 2% defined by the juncture between an inner constricted portion 31 and an outer larger portion 32. Disposed in the passageways 28 are forming punches 33, each having an enlarged head portion 34. that engages cam surface 24 on handle member 12 and a cylindrical body portion 36 integrally connected with the head portion 34 and being provided with a connector engaging tip 37. A spring member 38 located between the bottom surface of head portion 34 and the shoulder 29, urges the forming punch 33 into contact with the cam surface 24. It may be readily appreciated that rotation of the punch holder 26 in a clockwise direction will cause the cam surfaces 24 to force the forming punches 33 inwardly against the action of spring member 38. holder 26 is caused to rotate clockwise as handles 11 and 12 are brought together because of its connection with The punch the top handle side plates 14, 16 and clutch plate 39 positioned therebetween on both sides of the punch holder 26. This rotation is directly related to handle movement until an excessive force is applied, after which a clutch mechanism permits further handle movement without further punch holder rotation. Clutch plate 39 consists of a pair of rotatable faces 41 riveted, bolted or otherwise secured to punch holder 26 by fastening means 21 so as to rotate therewith and to prevent relative rotation there- 'between. The two faces 41 extend toward the handle ends of the tool and terminate with an integral transverse connector 43 upon which rollers 44 ride. Fastening means 21 extend outwardly from the faces 41 of the clutch plates and engage slots 19 in the top handle side plates 14, 16. Normally the fastening means 21 will engage the clockwise end 47 of the slots 19 and the clutch plate 39 and punch holder 26 will rotate in direct response to movement of handle 11 relative to handle 12. However, forces in excess of the desired crimping force on the punch tips 37 permit continued clockwise rotation of handle 11 without further rotation of the punch holder 26 or clutch plates 3?. When this happens the fastening means 21 engages the counterclockwise end 48'of the slots 19.

When a connector exerts a force against the punch tips 37, as when a larger size connector is being crimped, the frictional force between punch head 34 and cam surface 24 is too great to permit further relative movement therebetween, and prevents further rotation of the punch holder 26 and clutch plate 39. This fixes the position of the transverse connector 43 upon which roller 44 is adapted to move. The roller 44 is mounted at the pivotal connection 49 between bar 51, which is pivotally mounted to the top handle 11 at a point 52 slightly forward (to the left as shown in FIGURE 1) of the pivotal connection 49, and a plunger 53. This plunger 53 is telescopically engageable with a sleeve 54 which is pivotally seated in a socket 56 in the end of the top handle 11. A clutch retention spring 57 urges the sleeve 54 and plunger 53 apart and thus roller 44 forward to the position shown in the drawing. This retains the transverse connector 43 in its downwardmost position and the clutch plates 39 in clockwise position. The fastening means 42 connecting the clutch plates 39 and punch holder 26 to the top handle side plates 14, 16 are thus retained against the clockwise end 47 of the slots 45, all of which. is substantially as shown in FIGURE 1. When the connector pressure against the punch tips 37 exceeds a predetermined amount and the punch holder 26 and clutch plates 39 cease clockwise rotation, further closing of the handles 11, 12 may still be accomplished. This is done by the force of the transverse connector 43 on the clutch plates 39 against the rollers 44, causing rearward telescopic movement of plunger 53 against the force of spring 57. This rotates bar 51 counterclockwise about pivot 52 to a less vertical position, permitting further closing of the handles.

A feature of the present invention is that the handles must fully close before the connector being crimped can be released from the punch tips 37 and withdrawn from opening 18. This insures that a predetermined minimum crimping effect has taken place to securely connect the connector and its conductor together. A ratchet mechanism is provided for this purpose. Rack 58 has an arcuate inner surface 59 with notches 61 thereon and is pivotally mounted on lower handle 12. A pawl assembly 62 is pivotally mounted on fastener 63 to the top handle-side plates 14, 16. This assembly includes a triangular pawl 64 engageable with the notches 61 on rack 58 and a rearward extension 66 to which one end 67 of pawl assembly positioning spring 68 is attached. This spring 63 is of the compression type and, having its other end 69 fastened to the upper handle,continually urges rotation of the pawl assembly 62. When the rearward extension is below pivot point 63, the spring 63 urges clockwise rotation of the assembly, freeing pawl 64 from engagement with the notches 61. This happens only when the handles 11 and 12 are completely closed and pawl 64 is urged upwardly by contact with flat face 71 on the closed end of rack 58. When this is done the handles may again be separated, causing counter rotation of the punch holder 26 and Withdrawal of the punch tips 37 from engagement with the connector. When the handles are separated the flat surface 72 on the open end of rack 58 engages pawl 64 to cause counterclockwise rotation to lift the pawl extension 66 above pivot point 63. Spring 68 then urges further counterclockwise rotation to engage pawl 64 with the rack notches 61 for the next crimping operation.

Another feature of the present invention is the novel manner in which the crimping indentations are positioned along the axis of the connector. Positive stops are provided to limit inward movement of the connector into opening 18 for the various desired positions of the indentations along the axis. This is done with the connector depth selector mechanism 73 mounted on the other side of the opening 18 as shown in FIGURE '2. Here a knurled knob 74 is rotated until the proper color, desigmating the desired length, appears in the opening 76 in housing 77. A trigger 78, pivotally mounted on one of the top handle side plates 14, is actuated by a trigger thumb press 79 urged downwardly by the operator to permit an additional adjustment for a second crimp in axial spaced relation to the first crimp. This is more fully explained with reference to FIGURE 3.

The depth selector mechanism 73 shown in exploded form in FIGURE 3 provides for a depth selector plunger 81 with a plurality of recesses 82 of predetermined depth extending from its inner face 83. This depth selector plunger 81 rotates about plunger pin 34 so that the se-.

lected recess will become aligned with opening 18, shown in FIGURE 1, to receive the connector to be crimped. The depth of the selected recess determines how far the connector may be inserted, which in turn determines the axial spacing of the crimping indentations on the conductor. The plunger 31 consists of a cylinder having flats 86 on four sides to provide index for alignment of the recesses 82 with the connector opening 18. These flats are also color coded With proper nomenclature on the outside of the depth stop housing 77 to identifiy the type of connector to be used for the various positions of the plunger 53. The colored flats may be seen through a suitable opening 76' in the housing 77.

A depth selector plunger guide 87 retains the plunger 81 in its selected position. This guide is preferably of cylindrical configuration and is mounted on the tool in such manner that a central opening 88 in the guide is in axial alignment with the connector opening 18, shown in FIGURE 1. A transverse keyway 39 extends across the outer portion of the guide to receive the depth selector plunger 81 in non-rotatable condition, the keyway walls 91 being spaced substantially the thickness of the plunger 81 between opposing flats S6. The guide 87 is counter- -bored on its inner surface 92 to receive a plunger pin trigger plate 93 for axially spacing at second crimp as will be more fully described. A suitable aperture 94 spaced from the central opening 88 in the selector plunger guide 37 is for. the purpose of receiving the depth selector plunger pin 84 for pivotal and axial movement. A selector knob 74 is engageable through offset opening 96 in the face of the stop housing 77 with the stem 97 on the outer surface of the plunger 81. A spring 98 over the stem 97 abuts the outer surface of the plunger 81 and the inner wall of the housing 77 to urge the plunger 81 into the keyway 89 in the plunger guide $7 and the plunger pin 84 into contact with the outer surface of trigger plate 93. To make the proper depth selection the knob 74 is pulled outwardly to free the plunger 81 from engagement with the lceyway 89. The knob '74 is then rotat-ed (pin 34 in aperture 94 is in axial alignment with the knob 74) until the proper color appears in opening 75, whereupon the knob is released and spring 98 again seats the plunger 81 in keyway 89 to prevent further rotation.

The trigger 73 and trig er plate 93 provide for axial spacing of a second crimp as in the case of crim ing coaxial cable where n it is desired to crimp the conductor to both the conductor and the insulator portion. The trigger plate )3 consists of a circular disc with a hole 101 in the center and a wedge-shaped out 1592 radiating out from the hole. A small aperture 103 is placed the same distance from the center as the pin receiving aperture 94 in the plunger guide 37. Trigger tip 104 fits within the wedge-shaped cut 102. A suitable recess 106 is provided in the plunger guide 81 to permit movement of the trigger tip 194 therein for aligning aperture 101 in the trigger plate 93 with the aperture 04 in the plunger guide 31 to permit the plunger pin 84 to be urged therein by spring 98. This moves the connector in an axial direction in an amount equal to the thickness of the trigger plate 93 so that a second crimp may be made. As previously pointed out with reference to FIGURE 2, the trigger '78 is pivotally mounted and actuated by pressing the trigger thumb press 79 downwardly to rotate the trigger plate 93 until its aperture 101 is in alignment with the aperture 34 of the plunger guide.

While certain preferred embodiments of the invention have been specifically disclosed, it is understood that the invention is not limited thereto as many variations will be readily apparent to those skilled in the art and the invention is to be given its broadest possible interpretation within the terms or" the following claims.

1 claim:

1. Means for preselecting the axial position of crimping action upon a connector being crimped by a crimping tool comprising a depth selector mechanism for receiving the end of said connector being crimped, said mechanism comprising a plunger having a plurality of recesses therein of preselected depths, said plunger being rotatable to align one of said recesses with a connector receiving opening in said tool, a housing over said plunger, and a stem on said plunger extending outwardly from said housing for rotation of said plunger.

2. Means for preselecting the axial position of crimping action upon a connector being crimped by a crimping tool comprising a depth selector mechanism for receiving the end of said connector being crimped, said mechanism comprising a plunger guide positioned in alignment with a connector receiving opening in said tool, an opening in said guide in axial alignment with said connector receiving opening, a plunger having a plurality of recesses therein of preselected depths, said plunger being rotatable to align one of said recesses with both said openings, a housing over said plunger and guide, a stem on said plunger extending outwardly from said housing for axial and rotatable movement, resilient means urging said plunger into said guide, and means providing for a second axial spacing of crimping action upon said connector without further rotation of said plunger.

3. Means for preselecting the axial position of crimping action upon a connector being crimped by a crimping tool comprising a depth selector mechanism for receiving the end of said connector being crimped, said mechanism comprising a plunger guide positioned in alignment with a connector receiving opening in said tool, an opening in said guide in axial alignment with said connector receiving opening, and a plunger having a plurality of recesses therein of preselected depths, said plunger being rotatable to align one of said recesses with both said openings, a housing over said plunger and guide, a stem on said plunger extending outwardly from said housing for axial and rotatable movement, said housing having a plunger receiving opening for permitting axial movement of said plunger, resilient means urging said plunger into said guide, and means for axially spacing said plunger for a second axial spacing of crimping action upon said connector without further rotation of said plunger.

4. Means for preselecting the axial posit on of crimping action upon a connector being crimped by a crimping tool comprising a depth selector mechanism. for receiving the end of said connector being crimped, said mechanism comprising a plunger guide positioned in alignment with a connector receiving opening in said tool, an opening in said guide in axial alignment with said connector receing opening, a plunger having a plurality of recesses therein of preselected depths, said plunger being rotatable to align one of said recesses with both said openings, said guide being operable to receive and maintain said plunger in non-rotatable position, a housing over said plunger and guide, a stem on said plunger extending outwardly from said housing, said housing having a plunger receiving opening for permitting axial disengagement of said plunger from said guide to permit rotation of said plunger, resilient means urging said plunger into said guide, and means providing for a second axial spacing of crimping action upon said connector without further rotation of said plunger.

5. Means for preselecting the axial position of crimping action upon a connector being crimped by a crimping tool comprising a depth selector mechanism for receiving the end of said connector being crimped, said mechanism comprising a plunger having a plurality of recesses therein of preselected depths, said plunger being rotatable about a pin thereon to align one of said recesses with a connector receiving opening in said tool, a housing over said plunger, a stem on said plunger extending outwardly from said housing for axial and rotatable movement, said housing permitting axial movement of said plunger, resilient means urging said plunger inwardly, and means for axially spacing said pin in position said plunger for a second axial spacing of crimping action upon said connector without further rotation of said plunger.

References Cited by the Examiner UNITED STATES PATENTS 733,998 7/03 Richards 74-585 1,303,595 5/19 Rifflard 8 l-52.4 1,414,728 5/22 Enders 7417.5 2,086,400 7/37 Brenizer 8l15 2,524,343 10/50 Diener 74-470 2,552,602 5/51 Surline 33-181 2,572,013 10/51 Cushman 33181 2,577,199 12/51 Klopner 74-175 FOREIGN PATENTS 367,221 2/32 Great Britain.

ISAAC LISANN, Primary Examiner.

W. A. SCHEEL, Examiner. 

2. MEANS FOR PRESELECTING THE AXIAL POSITION OF CRIMPING ACTION UPON A CONNECTOR BEING CRIMPED BY A CRIMPING TOOL COMPRISING A DEPTH SELECTOR MECHANISM FOR RECEIVING THE END OF SAID CONNECTOR BEING CRIMPED, SAID MECHANISM COMPRISING A PLUNGER GUIDE POSITIONED IN ALIGNMENT WITH A CONNECTOR RECEIVING OPENING IN SAID TOOL, AN OPENING IN SAID GUIDE IN AXIAL ALIGNMENT WITH SAID CONNECTOR RECEIVING OPENING, A PLUNGER HAVING A PLURALITY OF RECESSES THEREIN OF PRESELECTED DEPTHS, SAID PLUNGER BEING ROTATABLE TO ALIGN ONE OF SAID RECESSES WITH BOTH SAID OPENINGS, A HOUSING OVER SAID PLUNGER AND GUIDE, A STEM ON SAID PLUNGER EXTENDING OUTWARDLY FROM SAID HOUSING FOR AXIAL AND ROTATABLE MOVEMENT, RESILIENT MEANS URGING SAID PLUNGER INTO SAID GUIDE, AND MEANS PROVIDING FOR A SECOND AXIAL SPACING OF CRIMPING ACTION UPON SAID CONNECTOR WITHOUT FURTHER ROTATION OF SAID PLUNGER. 